Airbag apparatus

ABSTRACT

A first airbag apparatus of the present invention has an airbag module, which includes an airbag and an inflator, and a displacement mechanism, which displaces the airbag module. The displacement mechanism displaces the airbag module from an original position to a predetermined position when a collision of the vehicle is predicted and displaces the airbag module from the predetermined position to the original position when the predicted collision is avoided. A second airbag apparatus of the present invention has the airbag module and the displacement mechanism, which displaces a support member. The support member displaces the airbag from the original position to the predetermined position before the airbag is deployed. The deployed airbag is supported between the support body that is displaced to the predetermined position and an occupant.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to an airbag apparatus mounted to avehicle.

[0002] As prior art airbag apparatus, Japanese Laid-Open PatentPublication No. 2001-206176 discloses an airbag apparatus 300 shown inFIGS. 29 to 31. As shown in FIG. 29, a first airbag module is providedin a door 210. The first airbag module includes a first inflator 288, afirst airbag 282, and a contacting plate 286. When a collision of thevehicle is predicted based on detection by a pre-crash sensor (notshown), the first inflator 288 is activated to deploy the first airbag282 toward the interior of a vehicle passenger compartment S as shown inFIG. 30. The deployment moves the contacting plate 286 toward theinterior of the passenger compartment S and pushes an occupant towardthe interior of the passenger compartment S.

[0003] A second airbag module is supported on the first airbag 282. Thesecond airbag module includes a second inflator 290 and a second airbag284. When the first airbag 282 is deployed, the second airbag module ispushed into the passenger compartment S. Thereafter, when a collisionsensor (not shown) detects a collision of the vehicle, the secondinflator 290 is activated and deploys the second airbag 284 between theoccupant and the door 210 as shown in FIG. 31. This reduces theinfluence of the impact of the collision to the occupant.

[0004] The second airbag 284 is projected into the passenger compartmentS in an undeployed state when the first airbag 282 is deployed. However,after being projected, the second airbag 284 is inflated on the unstablefirst airbag 282. Therefore, the second airbag 284, which chieflyprotects the occupant, can be inflated at a position that is notsuitable for protection. Even if the second airbag 284 is deployed at aposition corresponding to the occupant, the second airbag 284 can bedisplaced due to contact with the occupant and therefore cannoteffectively absorb the impact. Accordingly, the second airbag 284 cannoteffectively protect the occupant under certain circumstances.

[0005] The second airbag 284 moves toward the center of the passengercompartment S by the deployment of the first airbag 282, based on theprediction of a collision. If the collision is prevented after that, thefirst airbag module needs to be replaced to return the undeployed secondairbag 284 to the original position. However, it is almost impossiblefor an owner of the vehicle to replace the first airbag module.

SUMMARY OF THE INVENTION

[0006] Accordingly, it is an objective of the present invention toprovide an airbag apparatus that permits an undeployed airbag that hasbeen moved from the original position to return to the originalposition. Another objective of the present invention is to provide anairbag apparatus that expands an airbag in a suitable manner.

[0007] To achieve the above objective, the present invention provides anairbag apparatus mounted to a vehicle. The apparatus includes an airbag,an inflator, a first displacement mechanism, and a second displacementmechanism. The airbag is selectively displaced between an originalposition and a predetermined position. The airbag is initiallyundeployed. The inflator supplies gas into the airbag to deploy theairbag in a deployment direction. The first displacement mechanismdisplaces the undeployed airbag from the original position to thepredetermined position when a collision of the vehicle is predicted. Thesecond displacement mechanism displaces the undeployed airbag from thepredetermined position to the original position.

[0008] The present invention also provides an airbag apparatus mountedto a vehicle. The apparatus includes an airbag, an inflator, a supportbody, and a displacement mechanism. The inflator supplies gas into theairbag to deploy the airbag. The support body supports the airbag whendeployed and is selectively displaced between an original position and apredetermined position. The displacement mechanism displaces the supportbody from the original position to the predetermined position before theairbag is deployed. The deployed airbag is supported between the supportbody that is displaced to the predetermined position and an occupant.

[0009] A further aspect of the present invention is an airbag apparatusmounted to a vehicle. The apparatus includes an airbag, an inflator, asupport body, and a displacement mechanism. The inflator supplies gasinto the airbag to deploy the airbag. The support body supports theairbag when deployed. The displacement mechanism changes the relativeposition between the airbag and the support body from an originalposition to a predetermined position before the airbag is deployed. Thedeployed airbag is supported between the support body and an occupant inthe predetermined position.

[0010] Other aspects and advantages of the invention will becomeapparent from the following description, taken in conjunction with theaccompanying drawings, illustrating by way of example the principles ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The invention, together with objects and advantages thereof, maybest be understood by reference to the following description of thepresently preferred embodiments together with the accompanying drawingsin which:

[0012]FIG. 1 is a front view illustrating a steering wheel that has anairbag apparatus according to a first embodiment of the presentinvention;

[0013]FIG. 2 is a cross-sectional view taken along line 2-2 in FIG. 1;

[0014]FIG. 3 is an enlarged partial cross-sectional view illustratingpart of FIG. 2;

[0015]FIG. 4 is a block diagram showing parts of the airbag apparatusshown in FIG. 1 and parts relating to control of the airbag apparatus;

[0016]FIG. 5 is a side view illustrating a steering wheel that has anairbag apparatus according to a second embodiment of the presentinvention;

[0017]FIG. 6 is a perspective view illustrating a sheet that has anairbag apparatus according to a third embodiment of the presentinvention;

[0018]FIG. 7 is a front view, with a part cut away, illustrating theairbag apparatus shown in FIG. 6 and the vicinity of the airbagapparatus;

[0019]FIG. 8 is a perspective view illustrating a vehicle that has anairbag apparatus according to a fourth embodiment of the presentinvention;

[0020]FIG. 9 is a cross-sectional view illustrating the airbag apparatusshown in FIG. 8 and the vicinity of the airbag apparatus;

[0021]FIG. 10 is a partial side view illustrating a vehicle that has anairbag apparatus according to a fifth embodiment of the presentinvention;

[0022]FIG. 11 is a partial rear view illustrating the vehicle shown inFIG. 10;

[0023]FIG. 12 is a cross-sectional view illustrating the airbagapparatus shown in FIG. 10 and the vicinity of the airbag apparatus;

[0024]FIG. 13 is a cross-sectional view illustrating an airbag apparatusaccording to a sixth embodiment and the vicinity of the airbagapparatus;

[0025]FIG. 14 is a partial perspective view illustrating a vehicle thathas an airbag apparatus according to a seventh embodiment of the presentinvention;

[0026]FIG. 15 is a cross-sectional view illustrating the airbagapparatus shown in FIG. 14 and the vicinity of the airbag apparatus;

[0027]FIG. 16 is a cross-sectional view illustrating an airbag apparatusaccording to an eighth embodiment and the vicinity of the airbagapparatus;

[0028]FIG. 17 is a cross-sectional view illustrating an airbag apparatusaccording to a ninth embodiment and the vicinity of the airbagapparatus;

[0029]FIG. 18 is a cross-sectional view illustrating an airbag apparatusaccording to a tenth embodiment and the vicinity of the airbagapparatus;

[0030]FIG. 19 is a side view illustrating an airbag apparatus accordingto an eleventh embodiment and the vicinity of the airbag apparatus;

[0031]FIG. 20 is a front view illustrating the steering wheel shown inFIG. 19;

[0032]FIG. 21 is a cross-sectional view taken along line 21-21 in FIG.20;

[0033]FIG. 22 is a block diagram showing parts of the airbag apparatusshown in FIG. 19 and parts relating to the control of the airbagapparatus;

[0034]FIG. 23 is a side view illustrating an airbag apparatus accordingto a twelfth embodiment and the vicinity of the airbag apparatus;

[0035]FIG. 24 is a side view illustrating an airbag apparatus accordingto a thirteenth embodiment and the vicinity of the airbag apparatus;

[0036]FIG. 25 is a partial front view illustrating the steering wheelshown in FIG. 24;

[0037]FIG. 26 is a perspective view illustrating a vehicle that has anairbag apparatus according to a fourteenth embodiment;

[0038]FIG. 27 is a cross-sectional view illustrating the airbagapparatus shown in FIG. 26 and the vicinity of the airbag apparatus; and

[0039]FIG. 28 is a cross-sectional view illustrating an airbag apparatusaccording to a fifteenth embodiment and the vicinity of the airbagapparatus.

[0040]FIG. 29 is an enlarged partial cross-sectional view illustrating aprior art airbag apparatus in a non-activated state;

[0041]FIG. 30 is an enlarged partial cross-sectional view illustratingthe airbag apparatus shown in FIG. 29 when a collision is predicted; and

[0042]FIG. 31 is an enlarged partial cross-sectional view illustratingthe airbag apparatus shown in FIG. 29 when a collision occurs.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0043] A first embodiment of the present invention will now be describedwith reference to FIGS. 1 to 4.

[0044]FIGS. 1 and 2 show a steering wheel 21. The steering wheel 21 islocated inside a vehicle passenger compartment and includes a ringportion 22, a pad portion 23, and spoke portions 24 (three in the firstembodiment). The pad portion 23 is located at the center of the ringportion 22. The spoke portions 24 connect the ring portion 22 with thepad portion 23. The steering wheel 21 includes a core 25 made ofaluminum alloy and a core cover 26 made of soft synthetic resin. Thecore cover 26 covers the core 25. A fixing boss 27 is formed on part ofthe core 25, which is located at the center of the steering wheel 21.The steering wheel 21 is mounted to the distal end of a steering shaft28 with the fixing boss 27

[0045] The airbag module 29 is supported by three parts of the core 25that are located about the airbag module 29 at 120 degrees intervals.The airbag module 29 is located inside the pad portion 23. Therefore,the airbag module 29 rotates integrally with the steering wheel 21. Theairbag module 29 includes a folded airbag 31 and an inflator 32, whichsupplies gas to the airbag 31 to deploy the airbag 31. A slit (notshown) is formed on a portion of the surface of the pad portion 23opposite to the airbag 31. The airbag 31 opens the surface of the padportion 23 from the slit when deployed in expanded form to be exposedoutside the pad portion 23.

[0046] As shown in FIG. 3, brackets 29 a are located at the portions ofthe core 25 that support the airbag module 29. Each bracket 29 arotatably supports a ball joint 36. A threaded bore 36 a is formed atthe center of each ball joint 36. A support plate 34 is secured to eachpart of the core 25 that supports the airbag module 29. Each supportplate 34 rotatably supports a support shaft 33 via a bearing 35. Eachsupport shaft 33 has a threaded portion 33 a at the distal end and aworm wheel 33 b at the axially middle portion. Each threaded portion 33a is screwed to the threaded bore 36 a of the corresponding ball joint36. Each support plate 34 supports a motor 37. A worm 37 a, whichengages with the worm wheel 33 b of the corresponding support shaft 33,is formed on a rotary shaft of each motor 37. Therefore, each supportshaft 33 rotates in accordance with rotation of the rotary shaft of thecorresponding motor 37. When the support shaft 33 is rotated, thecorresponding bracket 29 a is shifted in the axial direction of thesupport shaft 33. Adjusting the position of each of the three brackets29 a with respect to the corresponding support shaft 33 causes theairbag module 29 to be displaced to change the direction inside the padportion 23.

[0047] A displacement mechanism is formed of three shifting mechanisms30. Each shifting mechanism 30 includes the bracket 29 a, the supportshaft 33, the support plate 34, the bearing 35, the ball joint 36, andthe motor 37. The displacement mechanism displaces the airbag module 29.The airbag apparatus includes the airbag module 29 and the displacementmechanism.

[0048] As shown in FIG. 4, a controller 40 is connected to the motors 37and the inflator 32 to control the operation of the motors 37 and theinflator 32. The controller 40 is further connected to a memory 41, arotational angle sensor 42, a pre-crash sensor 43, and a crash sensor44. The memory 41 stores data regarding the deployment direction of theairbag 31 suitable for the rotational angle of the steering wheel 21.The rotational angle sensor 42 detects the rotational angle of thesteering wheel 21 and sends a signal representing the rotational angleto the controller 40. The pre-crash sensor 43 is located at the front ofa vehicle and emits ultrasonic wave or electric wave forward to detectan object, such as another vehicle, approaching the vehicle from thefront. When detecting an object approaching the vehicle, the pre-crashsensor 43 sends a signal representing the distance between the objectand the vehicle to the controller 40. The controller 40 determines thedistance and the relative speed between the object and the vehicle andpredicts the possibility of a collision between the object and thevehicle based on the signal sent from the pre-crash sensor 43. The crashsensor 44 is located at the front of the vehicle. When an impact greaterthan or equal to a predetermined value is applied to the front of thevehicle, the crash sensor 44 sends a signal representing the collisionto the controller 40.

[0049] The airbag apparatus operates in the following manner. The airbagmodule 29 is normally located at an original position at which thedeployment direction of the airbag 31 is oriented in the axial directionof the steering wheel 21. When predicting a collision via the pre-crashsensor 43, the controller 40 rotates each motor 37 in accordance withthe rotational angle of the steering wheel 21 to displace the airbagmodule 29 in the optimal direction such that the deployment direction ofthe airbag 31 is oriented toward the driver's chest.

[0050] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. The airbag 31 is thendeployed such that the airbag 31 is deployed toward the driver's chest.On the other hand, when a collision is avoided, that is, when acollision is not detected during a predetermined time from when acollision is predicted, the controller 40 rotates the motors 37 andrestores the airbag module 29 to the original position.

[0051] If a collision is detected without any prediction of a collisionfor some reason, the controller 40 deploys the airbag 31, expanding itwith the airbag module 29 located at the original position.

[0052] The first embodiment provides the following advantages.

[0053] (1) When a collision is predicted, the airbag module 29 isdisplaced in the optimal direction such that the deployment direction ofthe airbag 31 is directed toward the driver's chest. Therefore, if acollision is detected subsequently, the airbag 31 is deployed toward thedriver's chest. Thus, the deployed airbag 31 effectively reduces theimpact applied to the driver at a collision and reliably protects thedriver from the impact of the collision.

[0054] (2) The airbag module 29 is displaced from the predeterminedposition to the original position when the predicted collision isavoided. That is, the airbag module 29, which includes the undeployedairbag 31, is allowed to easily return to the original position andprepare for a future collision.

[0055] (3) The displacement mechanism displaces the airbag module 29from the predetermined position to the original position in addition todisplacing the airbag module 29 from the original position to thepredetermined position. That is, the displacement mechanism functionsalso as a restore mechanism, which restores the airbag module 29 fromthe predetermined position to the original position. This simplifies thestructure of the displacement system of the airbag module 29.

[0056] A second embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0057] As shown in FIG. 5, the airbag module 29 according to the secondembodiment is firmly secured to the steering wheel 21. A support column47 extends from the proximal end of the steering shaft 28. The supportcolumn 47 can be bent at a joint portion 48 located at the axiallymiddle portion of the support column 47. The angle of the steering wheel21 changes in accordance with bending of the support column 47. A lockmechanism, which is not shown, locks the joint portion 48 to prevent thesupport column 47 from bending. The lock of the joint portion 48 by thelock mechanism is released when a collision is predicted by thepre-crash sensor 43.

[0058] A solenoid 49 is located below the steering wheel 21. A ring 49 bis fitted to the distal end of the support column 47. The solenoid 49has an armature 49 a, which is coupled to the ring 49 b. The 'solenoid49 is connected to the controller 40 instead of the motors 37 shown inFIG. 4. A displacement mechanism according to the second embodiment, isformed by the shifting mechanism 30, which includes the joint portion 48and the solenoid 49.

[0059] The steering wheel 21 and the airbag module 29 are normallylocated at an original position shown by a solid line in FIG. 5. If acollision is predicted by the pre-crash sensor 43, the controller 40releases the lock mechanism. The controller 40 then excites the solenoid49 to retract the armature 49 a. The support column 47 is bent at thejoint portion 48 to be arranged in a state shown by a chaindouble-dashed line in FIG. 5. As a result, the airbag module 29 isdisplaced to the optimal direction such that the deployment direction ofthe airbag 31 is oriented toward the driver's chest.

[0060] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. The airbag 31 is thendeployed toward the driver's chest. On the other hand, if the predictedcollision is avoided, the controller 40 extends the armature 49 a of thesolenoid 49 to restore the airbag module 29 to the original position.

[0061] The second embodiment provides the same advantages as the firstembodiment.

[0062] A third embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0063] In the third embodiment, the pre-crash sensor 43 is located at aside portion of the vehicle. The pre-crash sensor 43 emits ultrasonicwave or electric wave laterally from the vehicle to detect an object,such as another vehicle, approaching the vehicle from sideways. Thecrash sensor 44 is located at a side portion of the vehicle. When animpact greater than or equal to a predetermined value is applied to theside portion of the vehicle, the crash sensor 44 sends a signalrepresenting the collision to the controller 40.

[0064] As shown in FIGS. 6 and 7, the airbag module 29 and the solenoid49 are located in a backrest 51 a of a seat 51 inside the vehiclepassenger compartment. The airbag module 29 is coupled to an armature ofthe solenoid 49. The airbag module 29 selectively approaches andseparates from a body side portion 52 of the vehicle in accordance withthe extension and retraction of the armature. The solenoid 49 isconnected to the controller 40 instead of the motors 37 shown in FIG. 4.A displacement mechanism according to the third embodiment is formed bythe shifting mechanism 30, which includes the solenoid 49.

[0065] The airbag module 29 is normally located at a retracted positioninside the backrest 51 a, that is, an original position shown by a solidline in FIG. 7. If a collision is predicted by the pre-crash sensor 43,the controller 40 excites the solenoid 49 to extend the armature. Then,the airbag module 29 projects from the backrest 51 a to approach thebody side portion 52 as shown by a chain double-dashed line in FIG. 7.As a result, the deployment direction of the airbag 31 is orientedtoward the space between the body side portion 52 and the occupant.

[0066] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. Then, the airbag 31 isdeployed to expand toward the space between the body side portion 52 andthe occupant. On the other hand, if the predicted collision is avoided,the controller 40 retracts the armature to restore the airbag module 29to the original position.

[0067] The third embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment.

[0068] (4) If a collision is predicted, the airbag module 29 isdisplaced such that the deployment direction of the airbag 31 isoriented toward the space between the body side portion 52 and theoccupant. Therefore, if a collision is detected subsequently, the airbag31 is deployed toward the space between the body side portion 52 and theoccupant. Thus, the deployed airbag 31 effectively reduces the impactapplied to the occupant from the side of the vehicle at a collision andreliably protects the occupant from the impact of the collision.

[0069] A fourth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0070] In the fourth embodiment, the pre-crash sensor 43 is located onboth sides of the vehicle. Each pre-crash sensor 43 emits ultrasonicwave or electric wave toward the corresponding side of the vehicle todetect an object, such as another vehicle, approaching the vehicle fromthe corresponding side. The crash sensor 44 is located on both sides ofthe vehicle. Each crash sensor 44 sends a signal representing thecollision to the controller 40 when an impact greater than or equal to apredetermined value is applied to the corresponding side of the vehicle.

[0071] As shown in FIGS. 8 and 9, the airbag module 29 and a set ofsolenoids 49 are located on each of the left and right sides of an innerroof 54. The airbag modules 29 and the sets of solenoids 49 are coveredby a headlining 55 from below. Each set of solenoids 49 includes threesolenoids 49. The armature of each solenoid 49 is coupled to thecorresponding airbag module 29. Each airbag module 29 selectivelyapproaches or separates from the center of the vehicle passengercompartment in accordance with the extension and retraction of thearmatures of the corresponding set of solenoids 49. The solenoids 49 areconnected to the controller 40 instead of the motors 37 shown in FIG. 4.A displacement mechanism according to the fourth embodiment is formed bythe shifting mechanism 30, which includes the set of solenoids 49.

[0072] Each airbag module 29 is normally located at a retracted positioninside the headlining 55, that is, an original position shown by a solidline in FIG. 9. If a collision is predicted by either of the pre-crashsensors 43, the controller 40 excites the corresponding set of solenoids49 to extend their armatures 49 a. Accordingly, the corresponding airbagmodule 29 pushes away the headlining 55 and moves toward the center ofthe vehicle passenger compartment as shown by a chain double dashed linein FIG. 9. As a result, the deployment direction of the associatedairbag 31 is oriented toward the space between the corresponding bodyside portion 52 and the occupant instead of a garnish 57, which covers apillar 56.

[0073] If a collision is detected by either of the crash sensors 44subsequently, the controller 40 actuates the corresponding inflator 32.The associated airbag 31 is then deployed toward the space between thecorresponding body side portion 52 and the occupant. On the other hand,if the predicted collision is avoided, the controller 40 retracts thearmatures of the corresponding set of solenoids 49 to restore the airbagmodule 29 that has been displaced to the original position. The occupantcan return the headlining 55 that is pushed away when either one of theairbag modules 29 is shifted toward the center of the vehicle passengercompartment to the original position.

[0074] The fourth embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment and theadvantage (4) of the third embodiment.

[0075] (5) If either inflator 32 is actuated while the correspondingairbag module 29 is at the original position, the associated airbag 31interferes with the garnish 57 and is not deployed in an appropriatemanner. However, since each airbag module 29 is shifted toward thecenter of the vehicle passenger compartment when a collision ispredicted, each airbag 31 is prevented from interfering with the garnish57.

[0076] A fifth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0077] In the fifth embodiment, the pre-crash sensor 43 is located atthe rear of the vehicle. The pre-crash sensor 43 emits ultrasonic waveor electric wave toward the rear of the vehicle to detect an object,such as another vehicle, approaching the vehicle from the rear. Thecrash sensor 44 is located at the rear of the vehicle. When an impactgreater than or equal to a predetermined value is applied to the rear ofthe vehicle, the crash sensor 44 sends a signal representing thecollision to the controller 40.

[0078] As shown in FIGS. 10 to 12, the airbag module 29 and a rotarysolenoid 60 are located at a portion of the inner roof 54 at the rear ofthe vehicle and are covered by the headlining 55 from below. The airbagmodule 29 is secured to the inner roof 54 with links 59. The airbagmodule 29 is coupled to a drive shaft of the rotary solenoid 60 with oneof the links 59 and moves vertically in accordance with rotation of thedrive shaft. The rotary solenoid 60 is connected to the controller 40instead of the motors 37 shown in FIG. 4. A displacement mechanismaccording to the fifth embodiment is formed by the shifting mechanism30, which includes the links 59 and the rotary solenoid 60.

[0079] The airbag module 29 is normally located at a retracted positioninside the headlining 55, that is, an original position shown by a solidline in FIG. 12. If a collision is predicted by the pre-crash sensor 43,the controller 40 excites the rotary solenoid 60 to rotate the driveshaft. Accordingly, the airbag module 29 pushes away the headlining 55and moves downward as shown by a chain double-dashed line in FIG. 12. Asa result, the deployment direction of the airbag 31 is oriented in adirection parallel to the rear window 61.

[0080] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. The airbag 31 is thendeployed along the rear window 61. On the other hand, if the predictedcollision is avoided, the controller 40 releases the excitation of therotary solenoid 60 to restore the airbag module 29 to the originalposition. The occupant can return the headlining 55 that is pushed awaywhen the airbag module 29 is shifted downward to the original position.

[0081] The fifth embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment.

[0082] (6) If a collision is predicted, the airbag module 29 isdisplaced such that the deployment direction of the airbag 31 isoriented in a direction parallel to the rear window 61. Therefore, if acollision is detected subsequently, the airbag 31 is deployed along therear window 61. Thus, the deployed airbag 31 effectively reduces animpact applied to the occupant from the rear of the vehicle at thecollision and reliably protects the occupant from the impact of thecollision.

[0083] A sixth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0084] As shown in FIG. 13, in the sixth embodiment, the airbag module29 and the solenoid 49 are located below an instrument panel 63. Theairbag module 29 is coupled to the armature of the solenoid 49 with arotatable support plate 64. The airbag module 29 selectively approachesand separates from the legs of the occupant in accordance with theextension and retraction of the armature. The solenoid 49 is connectedto the controller 40 instead of the motors 37 shown in FIG. 4. Adisplacement mechanism according to the sixth embodiment is formed bythe shifting mechanism 30, which includes the solenoid 49 and thesupport plate 64.

[0085] The airbag module 29 is normally located at a position apart fromthe legs of the occupant, that is, an original position shown by a solidline in FIG. 13. If a collision is predicted by the pre-crash sensor 43,the controller 40 excites the solenoid 49 to extend the armature.Accordingly, the airbag module 29 approaches the legs of the occupant asshown by a chain double-dashed line in FIG. 13. As a result, the airbag31 is oriented toward the vicinity of the knees of the occupant.

[0086] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. Then, the airbag 31 isdeployed toward the vicinity of the knees of the occupant. On the otherhand, if the predicted collision is avoided, the controller 40 retractsthe armature of the solenoid 49 and restores the airbag module 29 to theoriginal position.

[0087] The sixth embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment.

[0088] (7) If a collision is predicted, the airbag module 29 isdisplaced such that the deployment direction of the airbag 31 isoriented toward the vicinity of the knees of the occupant. Therefore, ifa collision is detected subsequently, the airbag 31 is deployed towardthe vicinity of the knees of the occupant. Thus, the deployed airbag 31effectively protects the legs of the occupant from the impact of thecollision.

[0089] A seventh embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0090] As shown in FIGS. 14 and 15, in the seventh embodiment, theairbag module 29 and the solenoid 49 are located in the vicinity of thelower end of a front glass 66. A flexible cowl louver 67 covers theairbag module 29 from above. The airbag module 29 is coupled to thearmature of the solenoid 49 and moves vertically in accordance with theextension and retraction of the armature. The solenoid 49 is connectedto the controller 40 instead of the motors 37 shown in FIG. 4. Adisplacement mechanism according to the seventh embodiment is formed bythe shifting mechanism 30, which includes the solenoid 49.

[0091] The airbag module 29 is normally located at a retracted positioninside the cowl louver 67, that is, an original position shown by asolid line in FIG. 15. If a collision is predicted by the pre-crashsensor 43, the controller 40 excites the solenoid 49 to extend thearmature. Accordingly, the airbag module 29 pushes away the cowl louver67 and moves upward as shown by a chain double-dashed line in FIG. 15.As a result, the deployment direction of the airbag 31 is orientedtoward a region from the rear upper portion of a hood panel 68 to theupper portion of the front glass 66.

[0092] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. The airbag 31 is thendeployed toward the region. On the other hand, if the predictedcollision is avoided, the controller 40 retracts the armature of thesolenoid 49 and restores the airbag module 29 to the original position.

[0093] The seventh embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment.

[0094] (8) If a collision is predicted, the airbag module 29 isdisplaced such that the deployment direction of the airbag 31 isoriented toward the region from the rear upper portion of the hood panel68 to the upper portion of the front glass 66. Therefore, if a collisionis detected subsequently, the airbag 31 is deployed toward the region.Thus, if the vehicle runs over a pedestrian or crashes with atwo-wheeled vehicle, the deployed airbag 31 prevents the pedestrian or arider of the two-wheeled vehicle from hitting the rear portion of thehood panel 68 or the front glass 66. Consequently, the deployed airbag31 effectively reduces the impact applied to a collision object when thevehicle crashes with the object and reliably protects the collisionobject from the impact of the collision.

[0095] An eighth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0096] As shown in FIG. 16, in the eighth embodiment, the airbag module29 is supported by an under tray 70 located below the instrument panel63. The under tray 70 is coupled to the armature of the solenoid 49 andreciprocates forward and backward. The airbag module 29 selectivelyapproaches and separates from the legs of the occupant in accordancewith the extension and retraction of the armature. The solenoid 49 isconnected to the controller 40 instead of the motors 37 shown in FIG. 4.A displacement mechanism according to the eighth embodiment is formed bythe shifting mechanism 30, which includes the solenoid 49 and the undertray 70.

[0097] The airbag module 29 is normally located at a position close tothe legs of the occupant, that is, an original position shown by a solidline in FIG. 16. If a collision is predicted by the pre-crash sensor 43,the controller 40 excites the solenoid 49 to retract the armature.Accordingly, the airbag module 29 moves apart from the legs of theoccupant as shown by a chain double-dashed line in FIG. 16. At thistime, the airbag 31 is oriented toward the vicinity of the knees of theoccupant.

[0098] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. The airbag 31 is thendeployed toward the vicinity of the knees of the occupant. On the otherhand, if the predicted collision is avoided, the controller 40 extendsthe armature of the solenoid 49 to restore the airbag module 29 to theoriginal position.

[0099] The eighth embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment and theadvantage (7) of the sixth embodiment.

[0100] (9) After predicting a collision, a relatively wide space ismaintained between the airbag module 29 and the occupant. Therefore, theairbag 31 is efficiently deployed in the space during the actualcollision to effectively protect the legs of the occupant.

[0101] A ninth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0102] As shown in FIG. 17, in the ninth embodiment, the rotary solenoid60 is supported by the under tray 70 located below the instrument panel63. The airbag module 29 is coupled to an output shaft 60 a of therotary solenoid 60 and rotates integrally with the output shaft 60 a.The rotary solenoid 60 is connected to the controller 40 instead of themotors 37 shown in FIG. 4. A displacement mechanism according to theninth embodiment is formed by the shifting mechanism 30, which includesthe rotary solenoid 60.

[0103] The airbag module 29 is normally located at an original positionshown by a solid line in FIG. 17. The deployment direction of the airbag31 is oriented toward the substantially horizontal direction in theoriginal position. If a collision is predicted by the pre-crash sensor43, the controller 40 excites the rotary solenoid 60 to rotate theoutput shaft 60 a. Accordingly, the airbag module 29 is rotated slightlyupward from the original position as shown by a chain double-dashed linein FIG. 17. As a result, the deployment direction of the airbag 31 isoriented toward the vicinity of the knees of the occupant.

[0104] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. Then, the airbag 31 isdeployed toward the vicinity of the knees of the occupant. On the otherhand, if the predicted collision is avoided, the controller 40 releasesthe excitation of the rotary solenoid 60 and restores the airbag module29 to the original position.

[0105] The ninth embodiment provides the same advantages as the sixthembodiment.

[0106] A tenth embodiment of the present invention will now bedescribed. The differences from the first embodiment will mainly bediscussed below.

[0107] As shown in FIG. 18, in the tenth embodiment, the airbag module29 is mounted inside the instrument panel 63 on the passenger's side.The portion of the instrument panel 63 to which the airbag module 29 ismounted, or a lid 76, which closes an opening 69 located on theinstrument panel 63, is rotatable about a first shaft 71. A hinge 72extends from a portion of the lid 76 in the vicinity of the first shaft71. A solenoid 74 is located inside the instrument panel 63 and isrotatably supported by a second shaft 73. The armature of the solenoid74 is coupled to the hinge 72 with a third shaft 75. Therefore, when thesolenoid 74 is excited to extend or retract the armature, the lid 76 isrotated about the first shaft 71, which causes the airbag module 29 tobe displaced. The solenoid 74 is connected to the controller 40 insteadof the motors 37 shown in FIG. 4. A displacement mechanism according tothe tenth embodiment is formed by the shifting mechanism 30, whichincludes the first shaft 71, the hinge 72, the third shaft 75, the lid76, and the solenoid 74.

[0108] The airbag module 29 is normally located at a retracted positioninside the instrument panel 63, that is, an original position shown by asolid line in FIG. 18. If a collision is predicted by the pre-crashsensor 43, the controller 40 excites the solenoid 74 to retract thearmature. Accordingly, the lid 76 is rotated and the airbag module 29 isexposed outside the instrument panel 63 as shown by a chaindouble-dashed line in FIG. 18. As a result, the deployment direction ofthe airbag 31 is oriented toward the chest of the occupant in thepassenger's seat.

[0109] If a collision is detected by the crash sensor 44 subsequently,the controller 40 actuates the inflator 32. Then, the airbag 31 isdeployed toward the chest of the occupant in the passenger's seat. Onthe other hand, if the predicted collision is avoided, the controller 40extends the armature of the solenoid 74 and restores the airbag module29 to the original position.

[0110] The tenth embodiment provides the following advantages inaddition to the advantages (2) and (3) of the first embodiment.

[0111] (10) If a collision is predicted, the airbag module 29 isdisplaced such that the deployment direction of the airbag 31 isoriented toward the chest of the occupant in the passenger's seat.Therefore, if a collision is detected subsequently, the airbag 31 isdeployed toward the chest of the occupant in the passenger's seat. Thus,the deployed airbag 31 effectively reduces the impact applied to theoccupant in the passenger's seat at the collision and reliably protectsthe occupant in the passenger's seat from the impact of the collision.

[0112] An eleventh embodiment of the present invention will now bedescribed with reference to FIGS. 19 to 22. The eleventh embodiment hassubstantially the same structure as the second embodiment shown in FIG.5. The functions that are not explained in the second embodiment will bediscussed below.

[0113] As shown in FIGS. 19 to 21, a steering wheel 111 is locatedinside a vehicle passenger compartment and includes a ring portion 112,a pad portion 113, and spoke portions 114. The pad portion 113 islocated at the center of the ring portion 112. The spoke portions 114connect the ring portion 112 with the pad portion 113. The steeringwheel 111 includes a core 115 made of aluminum alloy and a core cover116 made of soft synthetic resin. The core cover 116 covers the core115. A fixing boss 117 is formed on part of the core 115, which islocated at the center of the steering wheel 111. The steering wheel 111is mounted to the distal end of a steering shaft 118 with the fixingboss 117.

[0114] An airbag module 119 is supported by the core 115 via a mountingplate 120 and is located inside the pad portion 113. The airbag module119 includes a folded airbag 121 and an inflator 122, which supplies gasto the airbag 121 to deploy the airbag 121.

[0115] As shown in FIG. 19, a support column 124 extends from theproximal end of the steering shaft 118 and can be bent at a jointportion 125 located at the axially middle portion. A solenoid 127 islocated below the steering wheel 111. An armature 127 a of the solenoid127 is coupled to a ring 124 a, which is fitted to the distal end of thesupport column 124.

[0116] When the airbag 121 is deployed, the deployed airbag 121 issupported between the steering wheel 111 (particularly the ring portion112 and the spoke portions 114) and an occupant P in the driver's seat(or a driver) . That is, the steering wheel 111 functions as a supportbody 123 for supporting the deployed airbag 121 against the occupant P.A displacement mechanism according to the eleventh embodiment is formedby a shifting mechanism 126, which includes the joint portion 125 andthe solenoid 127, and displaces the support body 123. The airbagapparatus includes the airbag module 119, the support body 123, and thedisplacement mechanism.

[0117] As shown in FIG. 22, a controller 128 is connected to thesolenoid 127 and the inflator 122 and controls the operation of thesolenoid 127 and the inflator 122. The controller 128 is furtherconnected to a memory 129, a pre-crash sensor 130, and a crash sensor131. The memory 129 stores data regarding control of the solenoid 127and the inflator 122. The pre-crash sensor 130 is located at the frontof a vehicle and emits ultrasonic wave or electric wave forward todetect an object, such as another vehicle, approaching the vehicle fromthe front. When detecting an object approaching the vehicle, thepre-crash sensor 130 sends a signal representing the distance betweenthe object and the vehicle to the controller 128. The controller 128determines the distance and the relative speed between the object andthe vehicle and predicts the possibility of a collision between theobject and the vehicle based on the signal sent from the pre-crashsensor 130. The crash sensor 131 is located at the front of the vehicle.When an impact greater than or equal to a predetermined value is appliedto the front of the vehicle, the crash sensor 131 sends a signalrepresenting the collision to the controller 128.

[0118] The airbag apparatus operates in the following manner. Thesteering wheel 111 is normally located at an original position shown bya solid line in FIG. 19. When predicting a collision by the. pre-crashsensor 130, the controller 128 excites the solenoid 127 to retract thearmature 127 a. Accordingly, the support column 124 is bent at the jointportion 125 so that the steering wheel 111 tilts as shown by a chaindouble-dashed line in FIG. 19 to face the chest of the occupant P.

[0119] If a collision is detected by the crash sensor 131 subsequently,the controller 128 actuates the inflator 122. The airbag 121 is thendeployed toward the chest of the occupant P. The deployed airbag 121 issupported between the steering wheel 111 and the chest of the occupantP. On the other hand, if the predicted collision is avoided, thecontroller 128 extends the armature 127 a of the solenoid 127 torestores the steering wheel 111 to the original position.

[0120] If a collision is detected without any prediction of a collisionfor some reason, the controller 128 deploys the airbag 121 with thesteering wheel 111 located at the original position.

[0121] The eleventh embodiment provides the following advantages inaddition to the advantages of the second embodiment.

[0122] (11) If a collision is predicted, the steering wheel 111 isdisplaced to face the chest of the occupant P in the driver's seat.Therefore, the deployed airbag 121 is stably supported between thesteering wheel 111 and the chest of the occupant P. This prevents theairbag 121 from bouncing back from the chest of the occupant P and beingdisplaced to an unsuitable position. Thus, the deployed airbag 121effectively reduces the impact applied to the occupant P at thecollision and reliably protects the occupant P from the impact of thecollision.

[0123] (12) When a collision is predicted, the steering wheel 111 isdisplaced from the original position to the predetermined position andwhen a collision is avoided, the steering wheel 111 is displaced fromthe predetermined position to the original position. That is, thesteering wheel 111 is reversibly displaced in accordance with thecondition of the vehicle.

[0124] (13) When the predicted collision is avoided, the steering wheel111 is automatically restored from the predetermined position to theoriginal position. Therefore, after the predicted collision is avoided,the driver is permitted to drive in the normal manner.

[0125] (14) The displacement mechanism not only displaces the steeringwheel 111 from the original position to the predetermined position butalso from the predetermined position to the original position. That is,the displacement mechanism functions also as a restore mechanism, whichrestores the steering wheel 111 from the predetermined position to theoriginal position. This simplifies the structure relating to thedisplacement of the steering wheel 111.

[0126] (15) Since the steering wheel 111 functions as the support body123, the structure of the airbag apparatus is simplified.

[0127] A twelfth embodiment of the present invention will now bedescribed. The differences from the eleventh embodiment will mainly bediscussed below.

[0128] As shown in FIG. 23, in the twelfth embodiment, the airbag module119 and the solenoid 127 are located inside the pad portion 113 of thesteering wheel 111. The airbag module 119 is coupled to the armature ofthe solenoid 127 and is displaced about a support shaft 134 inaccordance with the extension and retraction of the armature. Adisplacement mechanism according to the twelfth embodiment is formed bythe shifting mechanism 126, which includes the solenoid 127, anddisplaces the airbag module 119. In other words, the displacementmechanism changes the relative position between the steering wheel 111,or the support body 123, and the airbag module 119.

[0129] The airbag module 119 is normally located at an original positionshown by a broken line in FIG. 23. If a collision is predicted by thepre-crash sensor 130, the controller 128 excites the solenoid 127 toretract the armature. Accordingly, the airbag module 119 is displaced ina direction shown by an arrow in FIG. 23 such that the deploymentdirection of the airbag 121 is oriented toward the chest of the occupantP.

[0130] If a collision is detected by the crash sensor 131 subsequently,the controller 128 actuates the inflator 122. The airbag 121 is thendeployed toward the chest of the occupant P. The deployed airbag 121 issupported between the steering wheel 111 and the chest of the occupantP. On the other hand, if the predicted collision is avoided, thecontroller 128 extends the armature of the solenoid 127 and restores theairbag module 119 to the original position.

[0131] The twelfth embodiment provides the following advantages inaddition to the advantage (15) of the eleventh embodiment.

[0132] (16) If a collision is predicted, the airbag module 119 isdisplaced with respect to the steering wheel 111 such that the deployedairbag 121 is supported between the steering wheel 111 and the chest ofthe occupant P. Therefore, the deployed airbag 121 is prevented frombouncing back from the chest of the occupant P and being displaced to anunsuitable position. Thus, the deployed airbag 121 effectively reducesthe impact applied to the occupant P at the collision and reliablyprotects the occupant P from the impact of the collision.

[0133] (17) When the predicted collision is avoided, the airbag module119 is displaced from the predetermined position to the originalposition. Therefore, the airbag module 119, which includes theundeployed airbag 121, is permitted to easily return to the originalposition and prepare for the future collision.

[0134] (18) The displacement mechanism not only displaces the airbagmodule 119 from the original position to the predetermined position butalso from the predetermined position to the original position. That is,the displacement mechanism functions also as a restore mechanism, whichrestores the airbag module 119 from the predetermined position to theoriginal position. This simplifies the structure relating to thedisplacement of the airbag module 119.

[0135] A thirteenth embodiment of the present invention will now bedescribed. The differences from the eleventh embodiment will mainly bediscussed below.

[0136] In the thirteenth embodiment, as shown in FIGS. 24 and 25, ablank portion 136 is formed by cutting out a part of the ring portion112 of the steering wheel 111. The ring portion 112 of the steeringwheel 111 has two ends oriented toward the blank portion 136. A pair ofarcuate support members 137 is accommodated in the steering wheel 111.Each support member 137 is operably coupled to a rotary shaft of a motor138 located inside the steering wheel 111 via a pinion 139 and a rack140. Therefore, each support member 137 selectively projects from andretracts into the corresponding end of the steering wheel 111 inaccordance with the rotation of the rotary shaft of the correspondingmotor 138. The motors 138 are connected to the controller 128 instead ofthe solenoid 127 shown in FIG. 22.

[0137] The support body 123 according to the thirteenth embodimentincludes the steering wheel 111 and the support members 137. Adisplacement mechanism is formed by the shifting mechanisms 126, each ofwhich includes the motor 138, the pinion 139, and the rack 140, anddisplaces the corresponding support member 137.

[0138] The support members 137 are normally located at a retractedposition inside the steering wheel 111, that is, an original positionshown by a broken line in FIG. 25. If a collision is predicted by thepre-crash sensor 130, the controller 128 rotates the motors 138 so thatthe support members 137 project from the ends of the steering wheel 111as shown by a chain double-dashed line in FIG. 25. Accordingly, thesupport members 137, which project from the ends of the steering wheel111, abut against each other and fill the blank portion 136.

[0139] If a collision is detected by the crash sensor 131 subsequently,the controller 128 actuates the inflator 122. The airbag 121 is thendeployed toward the chest of the occupant P. The deployed airbag 121 issupported among the steering wheel 111, the support members 137, and thechest of the occupant P. On the other hand, if the predicted collisionis avoided, the controller 128 rotates the motors 138 to restore thesupport members 137 to the original position.

[0140] The thirteenth embodiment provides the following advantages.

[0141] (19) If a collision is predicted, the support members 137 aredisplaced such that the deployed airbag 121 is supported between thesupport members 137 and the chest of the occupant P. Therefore, thedeployed airbag 121 is stably supported among the steering wheel 111,the support members 137, and the chest of the occupant P. Thus, thedeployed airbag 121 is prevented from bouncing back from the chest ofthe occupant P and being displaced to an unsuitable position.Consequently, the deployed airbag 121 effectively reduces the impactapplied to the occupant P at the collision and reliably protects theoccupant P from the impact of the collision.

[0142] (20) If a collision is predicted, the support members 137 aredisplaced from the original position to the predetermined position andwhen the predicted collision is avoided, the support members 137 aredisplaced from the predetermined position to the original position. Thatis, the support members 137 are reversibly displaced in accordance withthe condition of the vehicle.

[0143] (21) The displacement mechanism not only displaces the supportmembers 137 from the original position to the predetermined position butalso from the predetermined position to the original position. That is,the displacement mechanism functions also as a restore mechanism, whichrestores the support member 137 from the predetermined position to theoriginal position. This simplifies the structure relating to thedisplacement of the support members 137.

[0144] A fourteenth embodiment of the present invention will now bedescribed. The differences from the eleventh embodiment will mainly bediscussed below.

[0145] In the fourteenth embodiment, the pre-crash sensor 130 is locatedon both sides of the vehicle. Each pre-crash sensor 130 emits ultrasonicwave or electric wave laterally from the vehicle to detect an object,such as another vehicle, approaching the vehicle from the correspondingside. The crash sensor 131 is located on both sides of the vehicle. Whenan impact greater than or equal to a predetermined value is applied toeither side of the vehicle, the corresponding crash sensor 131 sends asignal representing the collision to the controller 128.

[0146] As shown in FIGS. 26 and 27, two airbag modules 119 are locatedon the left and right sides of an inner roof 142 of the vehicle. Theairbag modules 119 are covered by a headlining 143 from below. Thevehicle has four doors 144 (only two are shown in FIG. 26). A side glass145 is accommodated in each door 144, and the glass 145 and door 144partly defines the vehicle passenger compartment. As shown by a chaindouble-dashed line in FIG. 27, the deployment direction of each airbag121 is oriented in a direction parallel to the inner side of the sideglasses 145 of the doors 144 on the corresponding side. The supportmember 137 in the fourteenth embodiment has a plate-like shape and isaccommodated in each door 144. Each support member 137 is coupled to amover of a linear motor 132 and moves vertically in accordance with themovement of the mover. The linear motors 132 are connected to thecontroller 128 instead of the solenoid 127 shown in FIG. 22.

[0147] In the fourteenth embodiment, the support members 137 function asthe support body 123. A displacement mechanism according to thefourteenth embodiment is formed by the shifting mechanism 126, whichincludes the linear motor 132, and displaces the support members 137.

[0148] The support members 137 are normally located at an originalposition shown by a broken line in FIG. 27. Each support member 137 isaccommodated in the corresponding door 144 in the original position. Ifa collision is predicted by the pre-crash sensor 130, the controller 128moves the mover of each linear motor 132 so that the correspondingsupport member 137 projects from the associated door 144. Accordingly,each support member 137, which projects from the corresponding door 144,covers the side glass 145 of the corresponding door 144 from inside.

[0149] If a collision is detected by the crash sensor 131 subsequently,the controller 128 actuates the inflator 122. Then, each airbag 121 isdeployed along the support member 137 that covers the side glass 145 ofthe corresponding door 144 from inside. Each deployed airbag 121 issupported between the corresponding support member 137 and the occupantP. On the other hand, if the predicted collision is avoided, thecontroller 128 moves the mover of each linear motor 132 to restore thecorresponding support member 137 to the original position.

[0150] The fourteenth embodiment provides the following advantages inaddition to the advantages (20) and (21) of the thirteenth embodiment.

[0151] (22) If a collision is predicted, each support member 137 isdisplaced such that the corresponding airbag 121 that has deployed issupported between the support member 137 and the occupant P. Therefore,each deployed airbag 121 is stably supported between the correspondingsupport member 137 and the occupant P and prevented from bouncing backfrom the occupant P and being displaced to an unsuitable position. Thus,each deployed airbag 121 effectively reduces the impact applied to theoccupant P at the collision and reliably protects the occupant P fromthe impact of the collision. In addition, at the actual collision, eachsupport member 137 covers the corresponding side glass 145 from theinside so that no force is directly applied to the side glass 145 fromthe inside of the vehicle passenger compartment.

[0152] A fifteenth embodiment of the present invention will now bedescribed. The differences from the eleventh embodiment will mainly bediscussed below.

[0153] As shown in FIG. 28, in the fifteenth embodiment, the airbagmodule 119 is accommodated inside an instrument panel 147 on thepassenger's side. An opening 148 is located at a portion of theinstrument panel 147 above the airbag module 119. The opening 148 isclosed by a lid 149. When deployed, the airbag 121 pushes open the lid149 and is exposed outside the instrument panel 147. The deploymentdirection of the airbag 121 is oriented toward the occupant P in thepassenger's seat.

[0154] The support member 137 is also accommodated inside the instrumentpanel 147 on the passenger's side. The support member 137 is coupled tothe mover of the linear motor 132 and projects from and retracts intothe instrument panel 147 in accordance with the movement of the mover.The linear motor 32 is connected to the controller 128 instead of thesolenoid 127 shown in FIG. 22.

[0155] In the fifteenth embodiment, the support member 137 functions asthe support body 123. A displacement mechanism according to thefifteenth embodiment is formed by the shifting mechanism 126, whichincludes the linear motor 132, and displaces the support member 137.

[0156] The support member 137 is normally located at an originalposition, which is inside the instrument panel 147, shown by a solidline in FIG. 28. If a collision is predicted by the pre-crash sensor130, the controller 128 moves the mover of the linear motor 132 so thatthe support member 137 projects from the instrument panel 147.Accordingly, the support member 137, which projects outside, covers afront glass 150 from inside as shown by a chain double-dashed line inFIG. 28. The front glass 150 partly defines the vehicle passengercompartment.

[0157] If a collision is detected by the crash sensor 131 subsequently,the controller 128 actuates the inflator 122. The airbag 121 is thendeployed toward the occupant P in the passenger's seat. The deployedairbag 121 is supported between the support member 137 and the occupantP. On the other hand, if the predicted collision is avoided, thecontroller 128 moves the mover of the linear motor 132 to restore thesupport member 137 to the original position.

[0158] The fifteenth embodiment provides the following advantages inaddition to the advantages (20) and (21) of the thirteenth embodimentand the advantage (22) of the fourteenth embodiment.

[0159] (23) The deployed airbag 121 is supported by not only the frontglass 150 but also by the support member 137. Therefore, the deployedairbag 121 is stably supported by the support member 137 and the frontglass 150. In addition, at the actual collision, the support member 137covers the front glass 150 from the inside so that no force is directlyapplied to the front glass 150 from the inside of the vehicle passengercompartment.

[0160] It should be apparent to those skilled in the art that thepresent invention may be embodied in many other specific forms withoutdeparting from the spirit or scope of the invention. Particularly, itshould be understood that the invention may be embodied in the followingforms.

[0161] The displacement mechanism that displaces the airbag module 29,119 or the support body 123 from the original position to thepredetermined position may be separate from the displacement mechanismthat restores the airbag module 29, 119 or the support body 123 from thepredetermined position to the original position.

[0162] In the airbag apparatus shown in FIG. 13, the support plate 64may be changed with a member that reciprocates forward and backward. Inthis case, the airbag module 29 approaches the legs of the occupant whena collision is predicted and separates from the legs of the occupantwhen the predicted collision is avoided in accordance with the extensionand retraction of the armature of the solenoid. Therefore, if acollision is predicted, the airbag module 29 is located close to thelegs of the occupant. Thus, although the airbag 31 is small, the airbag31 reliably protects the occupant. If the airbag 31 is small, the sizeof the airbag module 29 is reduced, which is suitable for mounting theairbag module 29 in the instrument panel 63 or in the vicinity of theinstrument panel 63.

[0163] In the airbag apparatus shown in FIG. 16, the airbag module 29may be supported by a dedicated support member located below theinstrument panel 63 instead of the under tray 70. In this case, thededicated support member is coupled to the armature of the solenoid 49and selectively moves forward and rearward.

[0164] In the airbag apparatus shown in FIG. 17, the rotary solenoid 60may be supported by a dedicated support member located below theinstrument panel 63 instead of the under tray 70.

[0165] In the above embodiments, the controller 40, 128 deploys theairbag 31, 121 if a collision is detected by the crash sensor 44, 131.However, the airbag 31, 121 may be deployed after a predetermined timefrom when the collision is predicted by the pre-crash sensor 43, 130. Inthis case, the crash sensor 44, 131 and the associated structure areunnecessary, which simplifies the structure. The controller 40, 128 mayalso be designed to deploy the airbag 31, 121 only when the pre-crashsensor 43 detects the object approaching the vehicle after apredetermined time from when the collision is predicted. In this case, amalfunction of the airbag apparatus is more reliably prevented.

[0166] In the above embodiments, the displacement mechanism fordisplacing the airbag module 29, 119 or the support body 123 from thepredetermined position to the original position operates automaticallyif the predicted collision is avoided. However, the displacementmechanism may be designed to operate when, for example, a restore switchlocated inside the vehicle is pressed.

[0167] The motor 37 included in the shifting mechanism 30, 126, whichforms the displacement mechanism, and other drive sources may be changedto other drive sources. For example, the solenoid 127 shown in FIG. 19may be changed to a motor, and a rack and a pinion, which are operablycoupled to the motor. The linear motor 132 shown in FIGS. 27 and 28 maybe changed to a motor, and a rack and a pinion, which are operablycoupled to the motor.

[0168] Therefore, the present examples and embodiments are to beconsidered as illustrative and not restrictive and the invention is notto be limited to the details given herein, but may be modified withinthe scope and equivalence of the appended claims.

1. An airbag apparatus mounted to a vehicle, the apparatus comprising:an airbag, which is selectively displaced between an original positionand a predetermined position, and which airbag is initially undeployed;an inflator, which supplies gas into the airbag to deploy the airbag ina deployment direction; a first displacement mechanism, which displacesthe undeployed airbag from the original position to the predeterminedposition when a collision of the vehicle is predicted; and a seconddisplacement mechanism, which displaces the undeployed airbag from thepredetermined position to the original position.
 2. The airbag apparatusaccording to claim 1, wherein the airbag and the inflator form oneairbag module, and wherein the first and second displacement mechanismsdisplace the airbag module.
 3. The airbag apparatus according to claim1, wherein the first displacement mechanism also serves as the seconddisplacement mechanism.
 4. The airbag apparatus according to claim 1,wherein the airbag is located inside a vehicle passenger compartment. 5.The airbag apparatus according to claim 4, wherein the airbag is locatedon a steering wheel of the vehicle, and wherein the deployment directionof the airbag that is displaced to the predetermined position isoriented toward a driver of the vehicle.
 6. The airbag apparatusaccording to claim 4, wherein the airbag is located at a backrest of aseat of the vehicle, and wherein the first displacement mechanismdisplaces the airbag such that the airbag projects toward a body sideportion of the vehicle from the backrest.
 7. The airbag apparatusaccording to claim 4, wherein the airbag is located below an instrumentpanel of the vehicle, and wherein the deployment direction of the airbagthat is displaced to the predetermined position is oriented toward thevicinity of an occupant's knees.
 8. The airbag apparatus according toclaim 4, wherein the airbag is located at an inner roof of the vehicle,and wherein the first displacement mechanism moves the airbag toseparate from the inner roof.
 9. The airbag apparatus according to claim8, wherein the airbag is located at part of the inner roof correspondingto both sides of the vehicle or corresponding to the rear of thevehicle.
 10. The airbag apparatus according to claim 8, wherein theairbag is located inside a headlining in the original position and isexposed outside the headlining in the predetermined position.
 11. Theairbag apparatus according to claim 1, wherein the airbag is locatedoutside a vehicle passenger compartment.
 12. The airbag apparatusaccording to claim 11, wherein the airbag is located in the vicinity ofa lower end of a front glass, and wherein the first displacementmechanism moves the airbag upward from a position lower than a rear endof a hood panel to a position substantially the same height as the rearend of the hood panel.
 13. An airbag apparatus mounted to a vehicle, theapparatus comprising: an airbag; an inflator, which supplies gas intothe airbag to deploy the airbag; a support body, which supports theairbag when deployed, and which is selectively displaced between anoriginal position and a predetermined position; and a displacementmechanism, which displaces the support body from the original positionto the predetermined position before the airbag is deployed, and whereinthe deployed airbag is supported between the support body that isdisplaced to the predetermined position and an occupant.
 14. The airbagapparatus according to claim 13, further comprising a restore mechanism,which displaces the support body from the predetermined position to theoriginal position.
 15. The airbag apparatus according to claim 13,wherein the displacement mechanism displaces the support body when acollision of the vehicle is predicted.
 16. The airbag apparatusaccording to claim 14, wherein the displacement mechanism serves also asthe restore mechanism.
 17. The airbag apparatus according to claim 13,wherein the support body is a steering wheel of the vehicle, and whereinthe airbag is located on the steering wheel.
 18. The airbag apparatusaccording to claim 13, wherein the airbag is arranged to deploy betweena surface that partly defines the vehicle passenger compartment and anoccupant, and wherein the support body that is displaced to thepredetermined position is located between the deployed airbag and thesurface that partly defines the vehicle passenger compartment.
 19. Anairbag apparatus mounted to a vehicle, the apparatus comprising: anairbag; an inflator, which supplies gas into the airbag to deploy theairbag; a support body, which supports the airbag when deployed; and adisplacement mechanism, which changes the relative position between theairbag and the support body from an original position to a predeterminedposition before the airbag is deployed, and wherein the deployed airbagis supported between the support body and an occupant in thepredetermined position.
 20. The airbag apparatus according to claim 19,further comprising a restore mechanism, which changes the relativeposition between the airbag and the support body from the predeterminedposition to the original position.
 21. The airbag apparatus according toclaim 19, wherein the displacement mechanism varies the relativeposition between airbag and the support body when a collision of thevehicle is predicted.
 22. The airbag apparatus according to claim 20,wherein the displacement mechanism serves also as the restore mechanism.23. The airbag apparatus according to claim 19, wherein the support bodyis a steering wheel of the vehicle, and wherein the airbag is located onthe steering wheel.